Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757295AbcCURIu (ORCPT ); Mon, 21 Mar 2016 13:08:50 -0400 Received: from down.free-electrons.com ([37.187.137.238]:39533 "EHLO mail.free-electrons.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1757232AbcCURIn (ORCPT ); Mon, 21 Mar 2016 13:08:43 -0400 From: Mylene JOSSERAND To: alexandre.belloni@free-electrons.com, rtc-linux@googlegroups.com Cc: Alessandro Zummo , linux-kernel@vger.kernel.org, mylene.josserand@free-electrons.com Subject: [PATCH 2/2] rtc: abx80x: handle the oscillator failure bit Date: Mon, 21 Mar 2016 18:06:10 +0100 Message-Id: <60a87de0ef65325fab65ecf897fc34df9641f188.1458579029.git.mylene.josserand@free-electrons.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2193 Lines: 77 Handle the Oscillator Failure ('OF') bit from Oscillator Status register (0x1D). This bit is cleared on set_time function and is read each time the date/time is read, but only in case of XT Oscillator selection. In RC mode, this bit is always set. Signed-off-by: Mylene JOSSERAND --- drivers/rtc/rtc-abx80x.c | 33 +++++++++++++++++++++++++++++++-- 1 file changed, 31 insertions(+), 2 deletions(-) diff --git a/drivers/rtc/rtc-abx80x.c b/drivers/rtc/rtc-abx80x.c index 0e4c9a0..ba0d619 100644 --- a/drivers/rtc/rtc-abx80x.c +++ b/drivers/rtc/rtc-abx80x.c @@ -58,6 +58,7 @@ #define ABX8XX_OSC_OSEL BIT(7) #define ABX8XX_REG_OSS 0x1d +#define ABX8XX_OSS_OF BIT(1) #define ABX8XX_OSS_OMODE BIT(4) #define ABX8XX_REG_CFG_KEY 0x1f @@ -138,7 +139,23 @@ static int abx80x_rtc_read_time(struct device *dev, struct rtc_time *tm) { struct i2c_client *client = to_i2c_client(dev); unsigned char buf[8]; - int err; + int err, flags, rc_mode = 0; + + /* Read the Oscillator Failure only in XT mode */ + rc_mode = abx80x_is_rc_mode(client); + if (rc_mode < 0) + return rc_mode; + + if (!rc_mode) { + flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); + if (flags < 0) + return flags; + + if (flags & ABX8XX_OSS_OF) { + dev_err(dev, "Oscillator failure, data is invalid.\n"); + return -EINVAL; + } + } err = i2c_smbus_read_i2c_block_data(client, ABX8XX_REG_HTH, sizeof(buf), buf); @@ -166,7 +183,7 @@ static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm) { struct i2c_client *client = to_i2c_client(dev); unsigned char buf[8]; - int err; + int err, flags; if (tm->tm_year < 100) return -EINVAL; @@ -187,6 +204,18 @@ static int abx80x_rtc_set_time(struct device *dev, struct rtc_time *tm) return -EIO; } + /* Clear the OF bit of Oscillator Status Register */ + flags = i2c_smbus_read_byte_data(client, ABX8XX_REG_OSS); + if (flags < 0) + return flags; + + err = i2c_smbus_write_byte_data(client, ABX8XX_REG_OSS, + flags & ~ABX8XX_OSS_OF); + if (err < 0) { + dev_err(&client->dev, "Unable to write oscillator status register\n"); + return err; + } + return 0; } -- 2.7.0